Inequalities (AQA A-Level Further Maths): Flashcards

When multiplying/dividing both sides by a negative number

$-x < -3$ (inequality flips)

No, not if $a$ or $b$ is negative

Values where numerator or denominator equals zero

$N$ and $D$ have same sign (both +ve or both -ve)

Where curve is above the x-axis

When $N = 0$ and $D \neq 0$

$N$ and $D$ have opposite signs

Solve each separately, then find intersection of solutions

For $\geq$ or $\leq$, where $f(x) = 0$